On a scorching day the peloton rode the 1.77 km ride from Castellón ending in a cruel ascent to Llucena.
Swiss rider Frank, part of 20 plus breakaway, jumped up the road along with the Astana rider Dario Caltaldo with 30km to go.
Caltaldo began to ache as some of the gradients hit 20 percent.
The chase was then taken up by Lotto rider Robert Gesink and Leopold König from team Sky.
Frank just had just enough in the tank to hold on for the win by six seconds.
Back down the road Alberto Contador launched a sharp attack, race leader Nairo Quintana followed as did Esteban Chaves. Christopher Froome was slow to pick up on the attack, but the four crossed the line together.
Quintana leads the race by 3.37 from Christopher Froome. (Euronews)